Drill-bit



G. A. HUMASON.

DRILL BIT.

APPLICATION FILED JAN. 24. 1919.

1,337,913. Patented Apr- 20, 1920.

UNITED STATES PATENT oFnIcE.

GRANVILLE A. HUMASON, OF HOUSTON, TEXAS, ASSIGNOR TO HUMASON ROLLER BIT COMPANY.

DRILL-BIT.

Application filed January 24, 1919. Serial No. 272,889.

To all whom it may concern:

he it known that I, GRANVILLE A. HUMA SON, a citizen of the United States, residing at Houston, in the county of Harris and State of Texas, have invented certain new and useful Improvements in Drill-Bits, of which the following is a specification.

This invention relates to new and useful improvements in a drill bit, and has particular relation to that type of bit which is specially adapted for use in drilling through rock, or other hard formations.

One object of the invention is to provide a bit of the character described, whose lower and operative end is provided with downwardly converging cutting rollers, which, in general contour, are substantially frusto-conical in form, but which may be varied in form, as desired.

A further feature of the invention resides in the provision of a bit of the character described, whoSe cutting rollers may be readily assembled with the bit, or detached therefrom.

IVith the above and other objects in view, the invention has particular relation to certain novel features of construction, operation and arrangement of parts, an example of which is given in this specification and illustrated in the accompanying drawings,

V wherein Figure 1, is aside elevation of the bit,

shown partially in section along the longitudinal central line.

Fig. 2, is a side elevation thereof, taken at right angles to the view shown in Fig. 1, and shown partially in section along the longitudinal central line.

, Fig. 3,is a bottom plan view, shown partially in section along a transverse central line.

Fig. 4, is a fragmentary sectional View, showing a modified form of cutting rollers.

Fig. 5, is, a fragmentary sectional view,- showing another form of cuttmg roller in elevation, and

Fig. 6, is a perspective view of mentioned form of roller. M

Referring now more particularly to the drawings wherein like numerals of reference designate similar parts in each of the figures, the numeral 1, refers to the head,

which has a central opening 2, extending down through the same, and contracted at its lower end, forming the abrupt shoulder Specification of Letters Patent.

the last Patented Apr. 20, 1920.

3. The upper end of this head is reduced, forming the shank 4:, which is internally threaded, thus providing for the attachment of the bit to the drill stem. Fitted through the lower reduced end of the opening 2, is the sleeve-like lining 5, whose upper end is flush with the shoulder 3, and fitted up through this lining is the spindle 6, whose lower end is formed with an annular shoulder 7, which fits against the corresponding shoulder, formed in the lower end of the head, and against which the lower end of the lining 5 rests. The lower end Fig. 5, the spindle is shown sectional, only one section thereof being shown. Integral with the lower end .of the spindle are the downwardly diverging bearing plates 11, and 12, which diverge at approximately, a 45 degree angle with the axis of the spindle. These bearing plates are provided with openings to receive the respective bearing pins 13, which extend therethrough at approximately right angles thereto. .These pins are formed integral with the lower ends of the corresponding dove tailed plates 14, which fit up into correspondingly formed grooves in opposite sides of the head. The upper ends of these plates abut against the shoulders 15, formed in the head, said shoulders serving to prevent an upward shearing strain upon the set bolts 16, by which the plates are secured against lengthwise movement, and threaded over the upper part of the head, and also of the plates is the locking ring 17, which, when threaded into position, serves to securely hold the plates in proper position. When thus secured, the lower end of this ring 17 abuts against the annular shoulders 18, which is formed by reducing the head and plates to accommodate of the said lining has an internally threaded spective cutters 22, 22, and threaded into the respective ends of each cutter, are the ring like nuts 23' and 24, clamped between which, and the ends of the journals 21, are felt washers 25 and26 which serve as lubricant retainers, and also exclude grit, and foreign matter from the bearings. The pins 13-proj'ect inwardly beyond the corresponding bearing plates 11 and 12, and threaded upon said projecting ends are the cup shaped journal bearings 27 which fit into cor= responding recesses in the conical shaped cutters 28, and said cutters are retained on the pins by means of the-.ringlike retaining nuts 29, which surround the pins and are threaded into said cutters, and clamped between the nuts 29, and the bearings 27, are

the felt washers 28, which serve as lubri-' cant retainers, and exclude grit and foreign matter from the bearings. If found desirable, set screws 30 may be threaded through the cutters 28, and their inner ends pro jected into alined annular grooves 31, 7 around the journal bearings 27. The plates 14 are provided with downwardly extending channels 32, which extend on through the pins. 13, through which a lubricant is ,con-

ducted to the bearings, passing from said channels through the orifices 33 and 34; It.

is to'be observed that before the cutters are fixed in position, the channel 32 may be filled with a lubricant, and a sufficient supply'will be thus retained on hand to lubricate the cutters during the period the bit willbe"retained in the well before sharpening, or pther repairs are required.

It w1ll-be observed that the cutters 22 are substantially cylindrical and the cutters- 28 are substantially conical shaped in'general contour, and having their sides cprrugateol or toothed, so as to readily abrade and disintegrate the formation encountered.

It will be further observed from an inspece tion of Fig. 1,.that the cutter 22 on one side is considerably longer than the corresponding cutter on the other side, audit-hat the cutters 28 are reversely proportioned. .Pro-

T vision is thus made for cutting away the formation opposite the outer ends of the bearing -plates Hand-12'; thecutter 22 opposite the bearing plate 11 cutting away that portion of the formation opposite said last rounded off, and in Figs. 5 and 6, the end cutters 2,8 are shown with blunt toothed ends. In the modified forms shown in Figs. 5 and 6, the peripheries of the cutters are formed with annular cutting ribs which are spaced apart, thus in effect, forming cutting disks, which abrade away and disintegrate the formation. This modified form of cutters will be found best adapted for use in certain kinds of formation.

Substantially cylindrical side reamers 26, 26, are mounted in suitable recesses in the head. These side reamers have toothed cut ting surfaces and rotate upon vertical axes, and project a short distance out beyond the head. They are preferably mounted oppo- .sitely between the boring cutters hereinabove described. These side reamers rotate upon the sleeve like journals 37, which are screwed upon the pins 38, extending'axially through the reamers. At one end, each reamer is shouldered in, forming annular shoulders 39, and c'lamped between said shoulders and the corresponding ends of the journals 37 are the felt washers 40. Threaded into the opposite ends of the disreamers, are the ring like nuts 41, and

bolts 45, and the plates 43 are further secured in position by means of the locking ring 17, which is threaded .thereover. The upper end of the pins 38 fit into correspondlng recesses 1n the lower ends of the plates" 43, and the. lower ends of said pins are seated in thebearin'gs formed in the ad- Y of the head beneath, and are joining face retained therein by meansof the detachable plugs 46, which are secured in position by means of the set screws 47. The bearings ofthe side reamers are lubricated by .means of a' lubricant previously placed in the channels 48, which extend downwardly through the plates 43, and on through the pins 38, and which turn outwardly and. discharge the lubricant into'the bearings through the orifices 49, provided in the journals 37.

In assembling the bit, the cutters 22 and 28 are first secured in position, and the sleeve 5 is then secured on the spindle 6.

The. plates 14 are then slid into their grooves, the sleeve 5 at the same timepassing up into the reduced end of the opening 2, and the spindle is secured in position as hereinbefore explained. The side reamers 36 are then secured to the head, and the side plates 14 and 43, are then secured in position as explained, and the bit is ready for operation. As stated, the spindle 6 may be formed of two sections in which case, the cutting rollers on each side may be secured in position separately. This form of construction is often preferable inasmuch as it permits the removal of a cutting roller singly for repairs, or replacement. Itv is obvious that any of the parts of the bit may be readily removed when it is desired to sharpen, repair or replace the same.

In operation, the rotation of the drill stem will cause the rotation of the drill bit attached thereto, causing the cutters 22 and 28 to roll on the bottom of the hole. This action, together with the weight of the stem be carried away by the stream of the flushing water projected downwardly through the stem, and the channels 50, and the same will be forced back upwardly through the bore around the drill'stem to the surface of the ground. It is clear that the form'a tion oppositethe bearing plate 11 will not be cut away by the adjacent cutter, but the opposite cutter 22 being somewhat longer than the adjacent cutter 22- will disintegrate and remove said formation and likewise that portion of the formation left opposite the bearing plate 12, will be cut away and removed by the opposite cutter 28, the same being made considerably longer than the adjacent cutter 28, so that the entire forma tion in the bottom of the hole will be gradually disintegrated and removed as the drill-- ing progresses. Meanwhile, the side ream- Y ers 36 will ream' out, enlarge and smooth the walls (if the bore, giving a uniform hole. This form of bit is capable of sustaining a great weight inasmuch 'as the bearing pins 13 are sustained not only at their bases, or

outer ends, but also near their inner ends, by the bearing plates 11 and 12, thus permitting the use of relatively long rolling cutters which conform perfectly to the contour of the bottom of the boregand rest thereon, thus preventing a wabbling of the bit, and conducing to the steady and uniform rotation thereof.

What I claim is:

1. A device of the character described, including a head, detachable plates" carried by opposite sides of the head, bearing pins converging from the lower ends of said plates toward the axial center of said head,

I detachable diverging bearing plates carried by the head and spaced from said lower and rotatable cutters mounted on said pins on each side of the respective bearing plates.

2. A device of the character described, including a head, having a longitudinal opening therethrough, a spindle fitted into said opening and secured in the head, and whose lower end is formed into diverging bearing plates, detachable plates secured on each side of the head, spindles integral with said last mentioned plates and converging downwardly toward the axial line of the head, said spindles extending through said bearing plates and rotatable cutters mounted on said respective spindles on opposite sides of the corresponding bearing plates.

3. A device of the character described, including a head, having a longitudinal open ing therethrough, a spindle fitted into said opening and secured in the head, and whose lower end is formed into diverging bearing plates, detachable plates secured on each side of the head, a locking ring threaded over said head and plates, and securing the latter to the former, spindles fixed to said last mentioned plates, and converging downwardly toward the axial line of the head, said spindles extending through said bearing plates, rotatable cutters mounted on said respective spindles on opposite sides of the corresponding bearing plates.

4:. A device of the character described, including a head, having a central opening, a spindle fitted into said opening and secured in the head, whose lower end is formed into diverging bearings, plates fitted into grooves cured in said head, whose lower end is' formed into diverging bearings, dovetailed plates fitted 1nt0 said grooves, whose lower ends are spaced from the corresponding bearings, a locking rlng threaded over sald head and plates, spindles converging from the lower ends of said plates-toward the axial center of the head and extending through said respective bearings, cutting I rollers mounted on said spindles between said plates and bearings, the roller on one side being longer than the corresponding roller on the other side, and cutting rollers mounted on the inner ends of said spindles,

the lengths of which are reversely proportioned to the lengths of the corresponding cutting rollers first mentioned.

6. A device of the character described, including a head, havin oppositely arranged grooves, and provide with a longitudinal central opening, a spindle fitted through said opening, and secured in said head, whose lower end is formed into diverging bearings, plates fitted into said grooves, whose lowerends are spaced from the'corresponding bearings, spindles converging from the lower ends of said plates toward the axial center of the head and extendlng through said respective bearings, cutting rollers mounted on said spindles between said plates and bearings, the roller on one side being longer than the corresponding roller on the other side, 'cutting rollers mounted on the inner ends of said spindles, the lengths of which are reversely proportioned to the lengths of thecorresponding cutting rollers first mentioned.

7. A device of the character described, in:

-cluding a head, bearing plates at the operative end of said head, said plates being spaced apart and each diverging downwardly from the axial line of the head, a bearing pin fixed to one of said plates at one end and whose. other end projects through the other plate, a rotatable cutter mounted on said pin between said plates, and a rotatable cutter mounted on the proend of said pin.

jectirig p 8. device of the character described, in-

eluding a head, oppositely disposed bearing pins carried by the operative end thereof, and converging downwardly toward the axial line of the head,a rotatable sectional cutter mounted on each pin, and detachable diverging bearing plates projecting from the head and located between the sections of the respective cutters, and through which the respective pins extend, said bearing plate beingI-detachably secured to the head.

9. n a drill bit, a head, a detachable bearing pin rigidly mounted therein, a rotatable cutter on said pin comprising two sections, one section being approximately cylindrical in shape and housed in a slot in the head, the other section inclosing the end of the pin and being conical in shape and a detachable bearing plate intermediate said sections of said cutter, and through'which the pin extends. 1

10. In a rotary boring drill, a head, a ro-" tatable cutter mounted on a' pin, inclined .downwardly, toward the longitudinal axis 

